Preheat and prep: Heat the oven to 425°F (220°C). Dry the pork and Brussels sprouts thoroughly with paper towels—moisture on the surface prevents proper browning. Set a meat thermometer nearby (highly recommended).

Season the pork: Lightly season the pork all over with 1/2 tsp kosher salt and 1/4 tsp black pepper, then rub in the chopped rosemary. The salt will begin to penetrate the meat while you prep the vegetables, helping flavor and retain juices.

Toss the sprouts: In a bowl, combine the 200 g halved Brussels sprouts with 1 tbsp olive oil, a pinch of salt and pepper, and the additional rosemary. Toss so each sprout is lightly coated—this oil and high oven heat will crisp the cut edges and caramelize sugars for deep flavor.

Roast the Brussels sprouts: Spread the sprouts cut-side down on a rimmed baking sheet in a single layer (use foil for easier cleanup). Roast in the preheated oven for 18–22 minutes, turning once halfway through. They should be deeply caramelized on the cut side and tender-crisp. Start them first because they take slightly longer than finishing the pork.

Sear the pork: While the sprouts begin roasting, heat a 10–12 inch ovenproof skillet over medium-high heat until shimmering. Add 1 tbsp olive oil. When it’s just smoking, add the pork and sear without moving for 1.5–2 minutes to develop a golden-brown crust—this Maillard reaction creates flavor and texture. Rotate and sear the other side about 1.5 minutes. Add the minced garlic in the last 30 seconds and spoon hot oil over the pork to fragrant the garlic but avoid burning it.

Finish the pork in the oven: Transfer the skillet with the seared pork to the oven and roast 6–10 minutes depending on thickness, until the internal temperature reaches 63°C (145°F) for medium with a slight pink center (USDA recommended minimum). Because the pork is small, check at the earlier end. Rest the pork loosely tented for 5–7 minutes after removing—it will carryover cook slightly and resting lets juices redistribute so slices stay juicy.

Make the apple-onion compote while pork rests: In a medium sauté pan set over medium heat, melt 1 tbsp butter until foamy. Add the sliced onion and a pinch of salt; sweat for 4–5 minutes until translucent and beginning to color—sweating draws sweetness out of the onion. Add the sliced apple and continue to cook 3–4 minutes so the apple softens but holds shape. Stir in 1 tsp honey to amplify natural sweetness and 1 tsp apple cider vinegar to add brightness and balance.

Deglaze and finish compote: Pour in 60 ml chicken stock and scrape the pan bottom to release browned bits—this fond is concentrated flavor from searing and will enrich the compote. Simmer gently until liquid reduces to a thick, glossy spoonable sauce (about 3–4 minutes). Taste and adjust seasoning—if it needs more acidity, add another 1/2 tsp vinegar; for more sweetness, a touch more honey.

Slice and plate: Thinly slice the rested pork across the grain into medallions to maximize tenderness. Spoon a generous portion of the apple-onion compote over the pork and arrange the roasted Brussels sprouts alongside. Finish with a drizzle of any pan juices from the pork skillet (strain if you like) and a few fresh rosemary leaves for aroma.

Serve immediately: Serve hot so the contrast between the warm compote, juicy pork, and crisp-tender sprouts is at its best.